Linear Excursion

[supa_c 5,000+ posts]

Question is...

Why dont they just list it as 4"p2p ?

 

[nametaken 10+ year member]

Where the **** did they say LINEAR excursion ??? 4" p-p out of either version of the W7 is not linear ...

Answer me this first, in order for you to get more output because of greater excursion does it have to be perfectly linear? And calm now on the atttitude, were on tEh InTRawebz. Your liek that guy that wants to diqualify a team becuase of minor technicalities even though their playing fair game. Eh, that wasnt that good of a example but whatever, its 4am.

Question is...Why dont they just list it as 4"p2p ?

They really dont have any info on the sub. Myabe when its released( i dont think its out yet) theylle have the full specs on it.

And doesnt that amp put out like 3600 rms? Thats liek 1800 a driver, i think its fair to say the dub7's been revamped.

 

[supa_c 5,000+ posts]

I bet that thing sounds nasty

The infamous " wooshy" sound from W7's would be quite loud

 

[Decipha 10+ year member]

hey nametaken... word of advice... don't argue with a mod, you may have trouble with future logins

 

[jellyfish420 10+ year member]

i like when they said" it'll move 2" p2p. but when you put it in a big room that needs to have more output it'll move 4" p2p."

what you don't need more power? it just sences how big the room is???

 

[nametaken 10+ year member]

Let's go over the entire conversation, shall we ?






1) This thread is named "Linear Excursion" ... Your first post implied linear excursion considering that's the name of the thread ... Thus the reason why I stated that it wasn't linear ...

2) After I stated that it wasn't linear, you defended it claiming it was, in fact, linear excursion. Now you've retracted that statement and, instead of admitting you're wrong, you said it's a minor technicality ...

3) You provide the video as proof, yet all it did was prove that they never actually said linear excursion

4) I never said that the excursion had to be linear in order to gain output. However, that gain in output from exceeding linear excursion also comes with a significant gain in distortion, too ...

5) Using "the ****" is giving attitude ?

1) Listen, nowhere does is say its not linear so if you wanna get technical ill stick to what im thinking, hell if your doing it no reason for me not too. Im willing to bet once the spes are published it will have an xmax in the upper 40's,not exactly 50(for that 4" p2p).

2) And jeez, as i had nothing(neither do you if wanna get technical) i kept bringing up "its what the engineers said", "according to them", i thought i made it clear that it was hear say type information, not written down anywhere. I mean i even said

They really dont have any info on the sub. Myabe when its released( i dont think its out yet) theylle have the full specs on it.

to supa c

3) I used it as what they claimed. And again like i said I think JL is better than lying about what a sub can do. If you dont, well obviously thats your opinion.

4) I never said you did, i was askign you a question. So even if it might interfere with how its sounds (might //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif ) it still capable of USING that 4 inches at one point. But if to them, the dub7 uses this 4 inches and it such an awesome sounding sub(again..to them) then mayeb that 50mm is linear.

5) And really, you saying F U C K where it isnt needed at all, not attitude. ? Eh, i guess i was brought upa little different.

Maybe i put a little too much trust in what JL says, but liek ive said too many times before, i think theyre professional enough to not have to lie and/or exagerate claims.

And Supa C, whats wrong with arguing with mods, theie poeple too. Even if i am wrong i did learn something, and mayeb others did too, thats the main reason i visit forums.

edit: i mean decipha

 

[UndercoverPunk 5,000+ posts]

Jesus Jmac, didn't know I couldn't joke around with Kephart...

 

[AznRevlAzn 10+ year member]

the are you constantly calling thr w7 dub7? IMO your giving it a bad Audiobahn esque feature.

And i am 100% behind Jmac. I am not *******, it's because in the past he is literally never ever wrong.

 

[FOSGATE JOE 10+ year member]

l.o.l caraudio geeks at war //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif//content.invisioncic.com/y282845/emoticons/popcorn.gif.32dd9e22fd77e77bc3c907062768fcd2.gif :swordfigh

 

[mega1268 10+ year member]

What does the guy mean........ it has 2 inch peak to peak then it can "shift gears" and go to 4 inch p2p........ wtfs that supposed to mean. W7 has a sub tranny for bigger rooms.

 

[nametaken 10+ year member]

the are you constantly calling thr w7 dub7? IMO your giving it a bad Audiobahn esque feature.
And i am 100% behind Jmac. I am not *******, it's because in the past he is literally never ever wrong.

Yea it does sound audiobahnesque i admit, but i was geting bored //content.invisioncic.com/y282845/emoticons/veryhappy.gif.fec4fed33b4a1279cf10bdd45a039dae.gif

Haha, havent seen hiw wrong either.

What does the guy mean........ it has 2 inch peak to peak then it can "shift gears" and go to 4 inch p2p........ wtfs that supposed to mean. W7 has a sub tranny for bigger rooms.

The gotham/fathom(i think too) can be set specifically for your room. So in a very small room it might not have to use all that 4" to get the bass needed. But when set in a big room and it needs that xtra output for a loud explosion, i guess its starts pumping out 3600rms to get that excursion.

Speaking of which, in order for you to have that muchpower youde need ALOT of current, more than a house could provide. SO maybe instead of using tons of amperage mayeb they use voltage instead. But this would mean that the impedance of the subs would have to be higher correct(i think the average outlet can only provide soemthing like 15 amps?). Im too hungry to do the math, i need to eat breakfast.

 

[JimJ 5,000+ posts]

I would assume that a true 3.8kW home audio amplifier will be 220V, as the current draw on a 120V single-phase circuit would be way, way too much. Even at 80% efficiency, that's still over 50 amps of current draw. Most residential 120V circuits max out at 25A...

 

[its_bacon12 10+ year member]

word....

dass alotta power //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

maybe its more suitable to theatres? where they have the power to supply

 

[80INCHES 5,000+ posts]

What does the guy mean........ it has 2 inch peak to peak then it can "shift gears" and go to 4 inch p2p........ wtfs that supposed to mean. W7 has a sub tranny for bigger rooms.

//content.invisioncic.com/y282845/emoticons/rotflol.gif.b453361716769b8110ddefc85ff03cd2.gif//content.invisioncic.com/y282845/emoticons/hilarious.gif.02a037aad04aa96f19982b298a3d70a8.gif

good point

80

 

[supa_c 5,000+ posts]

I would assume that a true 3.8kW home audio amplifier will be 220V, as the current draw on a 120V single-phase circuit would be way, way too much. Even at 80% efficiency, that's still over 50 amps of current draw. Most residential 120V circuits max out at 25A...

There is an old thread on what kind of electrical system you would need in your house to run this thing.

 

[audioholic 5,000+ posts]

The excursion specs the JL guys talked about in that video were always referred to as "peak to peak". This is NOT linear, this is physically how far a subwoofer is capable of moving. Are the great guys at JL lying? No. But they are not speaking about linear excursion either. Which is rather confusing/deceiving. Sorry nametaken, but you've utterly 100% wrong from the get-go. And furthermore, if JL is so proud of their sub, why do they refer only to P2P specifications? Its a BS advertising video for people who know nothing about subwoofers. That is the LAST place you should be drawing your 'facts' from. lol

 

[nametaken 10+ year member]

The excursion specs the JL guys talked about in that video were always referred to as "peak to peak". This is NOT linear, this is physically how far a subwoofer is capable of moving. Are the great guys at JL lying? No. But they are not speaking about linear excursion either. Which is rather confusing/deceiving. Sorry nametaken, but you've utterly 100% wrong from the get-go. And furthermore, if JL is so proud of their sub, why do they refer only to P2P specifications? Its a BS advertising video for people who know nothing about subwoofers. That is the LAST place you should be drawing your 'facts' from. lol

*Sigh*

Just to show the mass people how much the thing can move(and i acknowledge its marketing, never said it wasnt), them saying its moves 40mm one way would kinda be //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif for regular folks(again, its marketing i know). And i never said it was a fact, please show me where i said it. I even stated it was hear say(no specs about the sub), but i doubt theyde lie so thats why i gave them the benefit of the doubt. And like i said before, it probably doesnt move 50mm but maybe higher 40's, which is still an assload.

 

[nametaken 10+ year member]

You're right that the voltage will, most likely, be higher than a typical outlet (Most likely 220 volt as Jack said) because most houses wouldn't be able to supply the current without serious upgrades to their electrical systems.
Efficiency = Power Out/Power In

Current = Power/Voltage

At 60% efficiency (approximate efficiency of the 1000/1), you'd be looking at:

0.6 = 3800/Power In

Power In = 3800/0.6

Power In = 6333.333 watts

With a 110 volt outlet, this translates to 6333.333/110 = 57.576 amperes ...

With a 220 volt outlet, this translates to 6333.333/220 = 28.788 amperes ...

The voice coil's resistance, however, will only affect the voltage on the amplifier outputs, though //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Ahh. So a sub isnt seing much current, just the amp?

 

[audioholic 5,000+ posts]

*Sigh*
Just to show the mass people how much the thing can move(and i acknowledge its marketing, never said it wasnt), them saying its moves 40mm one way would kinda be //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif for regular folks(again, its marketing i know). And i never said it was a fact, please show me where i said it. I even stated it was hear say(no specs about the sub), but i doubt theyde lie so thats why i gave them the benefit of the doubt. And like i said before, it probably doesnt move 50mm but maybe higher 40's, which is still an assload.

I dont know what the sigh was for, you seem to be acknowledging that everything I said was true.

 

[nametaken 10+ year member]

I dont know what the sigh was for, you seem to be acknowledging that everything I said was true.

I sighed because i have to explain something that i really dont have to, if you really took the time to read what i wrote i wouldnt have to break it down. And i didnt acknowledgs everything, just clearing up for you what i really did say/imply.

Ohm's Lawower = Voltage*Current

Power = Voltage*Voltage/Resistance

Power = Current*Current*Resistance

3800 watts into a 3 ohm load would be: 3800 = I^2*3, I = Sqrt(3800/3), I = 35.590 amperes. V = 106.771 volts

So the amp would pull 28.788 amperes of current from the outlet at 220 volts to output 35.59 amperes of current at 106.771 volts to the subwoofer ...

Of course, this won't be completely correct as the driver doesn't have a static resistance. Instead, it has impedance which fluctuates with frequency.

Ahh, its all coming back to me, physics class is kinda fuzzy, must be the summer break //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif